The objective of this core TR&D project is to-develop a system with the necessary enhancements in resolution, speed and sensitivity to provide users with an electronic readout device comparable to or better than film. This sub project is very important to this research program as it will allow us to improve the image acquisition rate and precision for computerized 3-D reconstruction and visualization of thick biological specimens. There are three areas of project activity in which we briefly report progress: has continued and we succeeded in intermediate voltage EM [see "Performance thin foil scintillating screen for transmission electron microscopy" (Fan, Dunkelberger and Ellisman, Ultrarnicroscopy 55:7-14, 1994). We also received word from the US patent office that claims were allowed for a second scintillating screen system described in our publication "Performance characteristics of radioluminescent fiber optics as electron scintillators" (Fan et at, J Electron Microscopy 42:419-423, 1993). This system is less useful for the higher accelerating voltages employed at NCMIR but will be useful for lower KeV EM and digital mammography. Our coinventors, Lockheed-Martin Corp., are currently looking to license this device for these purposes. We also developed a method for deposition of phoshor to make uniform scintillating screens for TEM and a patent application has been filed pertaining to this process. This method is important because it will enable us to make the large uniform screens necessary for the camera system we are building. 2) A new lens relay system has been developed working with two companies, "Optical Research Associates" and "Tinsley Optics". Together we have completed the specifications and design of a relay lens system for the IVEM's new large format direct digital camera project. We looked at many options and have just issued the purchase order to have the custom lense built according to the details of the design. 3) A CCD imager and camera head has been selected after considerable study and design specification work. We have entered into collaborations with Photometrics and MJT's Lincoln Laboratory to assemble a "state-of-the-art" camera head. The CCD chip is being provided by Lincoln Labs and Photometrics will build the camera head itself. Meanwhile Tinsley will build the lens and the UCSD machine shop will fabricate several parts needed to integrate the system with the microscope. Although the camera head will take about 7 months to build we expect to have preliminary results with the system for the next progress report.